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Finding the Fourth Proportional to 528.08, 728.58 and 318.20

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Solution

The fourth proportional to 528.08, 728.58 and 318.20 is: 439.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.08 : 728.58 = 318.20 : x
  2. Step 2: Convert to fraction form
    528.08/728.58 = 318.20/x
  3. Step 3: Cross multiply
    528.08x = 728.58 × 318.20
  4. Step 4: Simplify right side
    528.08x = 231,834.16
  5. Step 5: Solve for x
    x = 231,834.16/528.08
  6. Step 6: Final answer
    x = 439.01

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.